[Sep-2019-18] Up To Date 1z0-485 Free Practice Questions

To ensure redundancy during a rolling upgrade of the Exadata Storage Server Software, MAA recommends ASM high redundancy disk groups.

ASMDeactivationOutcome – recall that grid disks can be deactivated, which is effectively taking them offline. Since ASM mirroring ensures that the data is located on another disk, making this disk offline does not lose data. However, if the mirror is offline, or is not present, then making this grid disk offline will result in loss of data. This attribute shows whether the grid disk can be deactivated without loss of data. A value of “Yes” indicates you can deactivate this grid disk without data loss.
CellCLI

The following bottlenecks will be reached first if using InfiniBand fabric to media server:
1. Media server to tape library SAN transfer rate
2. Number of tape drives

Using the Database Resource Manager, you can:
Distribute available processing resources by allocating percentages of CPU time to different users and applications. In a data warehouse, a higher percentage may be given to ROLAP (relational on-line analytical processing) applications than to batch jobs.

There are three values the CELL_FLASH_CACHE attribute can be set to.
DEFAULT specifies the cache used for a DEFAULT object is automatically managed as described in the previous section. NONE specifies that the object will never be cached. KEEP specifies the object should
be kept in cache.
Note: The CELL_FLASH_CACHE can be assigned to a database table, index, partition and LOB column.

In earlier releases, database administrators had to mark an object as KEEP to have it cached in flash cache for large scan workloads. This feature primarily benefits table scan intensive workloads such as Data Warehouses and Data Marts. Random I/Os such as those performed for Online Transactional Processing (OLTP)
continue to be cached in the flash cache the same way as in earlier releases.
Note: With the Exadata Storage Server Software 11.2.3.3.0 and above, the Exadata Smart Flash Cache
software automatically caches objects read, in large table scans, in the flash cache based on how
frequently the objects are read. Previously, the default behavior was to bypass the flash cache for
such large sequential scans.

B: Exadata storage version 11.2.3.2.1 is the minimum version required to use this write back flash cache option.
C: Steps for Enabling Write back flash cache:
First of all, you don’t need the stop CRS or database (This is ROLLING method) ,you can do it cell by cell.
* drop flashcache
* Be sure asmdeactivationoutcome is YES is before disabling grid disk

Smart Flash Logging takes advantage of the flash memory in Exadata storage to speed up log writes.

IORM is similar to Oracle Database Resource Manager (DBRM) in that it provides a means for controlling allocation of system resources. Where DBRM’s primary goals are to control CPU resources, limit the degree of parallelism, and impose resource consumption constraints for different types of sessions within an Oracle database, IORM’s goal is to govern I/O resource allocations between databases on a shared storage infrastructure. When consolidating Oracle databases on Exadata, IORM can be used to ensure that I/O is controlled between databases as well as classifications of consumes that utilize the same ASM disk infrastructure and, as such, provide resource control capabilities beyond what DBRM provides within a database.
/ Using the Database Resource Manager, you can:
* Guarantee certain users a minimum amount of processing resources regardless of the load on the system and the number of users
* Distribute available processing resources by allocating percentages of CPU time to different users and applications. In a data warehouse, a higher percentage may be given to ROLAP (relational on-line analytical processing) applications than to batch jobs.
* Limit the degree of parallelism of any operation performed by members of a group of users etc

C: Oracle Exadata is architected to scale-out to any level of performance. To achieve higher performance and greater storage capacity, additional database servers and Exadata cells are added to the configuration – e.g., Half Rack to Full Rack upgrade. As more Exadata cells are added to the configuration, storage capacity and I/O performance increases near linearly.
E: Oracle\'s interconnect protocol uses direct data placement (DMA – direct memory access) to ensure very low CPU overhead by directly moving data from the wire to database buffers with no extra data copies being made. The InfiniBand network has the flexibility of a LAN network, with the efficiency of a SAN.
Incorrect:
Not A: The architecture of the Exadata solution includes components on the database server and in the Exadata cell. The software architecture for a Quarter Rack configuration is shown below.

Not B: No cell-to-cell communication is ever done or required in an Exadata configuration. Not D: Each InfiniBand link provides 40 Gigabits of bandwidth –

Note: The Sun ZFS Backup
Appliance has extremely fast backup and restore throughputs, ensuring that backup windows
and recovery time objectives (RTOs) are met by providing timely recovery in the event of a disaster
Incorrect:
Not A, Not E: compression is a factor

A: Zero Downtime Migration to Oracle Exadata using Oracle GoldenGate
– Reduce downtime for any method
– Zero data loss fallback
– Phased migration
E: Cross Platform Incremental Backups
– Reduce downtime for Transportable Tablespaces

There are total two category of network switches used to prepare computing environment inside the rack.
* InfiniBand Switches - two models used depending on requirements Sun Oracle 36-port InfiniBand Switch
Sun Oracle InfiniBand Gateway Switch
* Ethernet Switch - primarily for management purposes Cisco Catalyst 4948

Common information that applies to both of these InfiniBand switches Form Factor: One rack unit (1U) height
Power Supplies: Two Cooling Fans: Five
IB Subnet Management: Yes Firmware Upgradeable: Yes
Command Line Access: Yes. Via ssh and usb-serial access Web Based Management: Yes
SNMP Access: Yes
As you might have figured out by now that the IB Gateway switch is almost like a super set of 36-port switch in terms of features and capabilities.
Incorrect:
Not E: Since the Exadata hardware cannot be modified, it is not supported to add HBA cards to any of the Exadata servers. It is supported to present storage via the network ports on the database servers via NFS or iSCSI, although Fibre Channel over Ethernet (FCoE) is not supported.

The Exadata Smart Flash Cache feature of the Exadata Storage Server Software intelligently caches database objects in flash memory, replacing slow, mechanical I/O operations to disk with very rapid flash memory operations. .

A: CELLSRV (Cell Services) is the primary component of the Exadata software running in the cell
and provides the majority of Exadata storage services. CELLSRV is multi-threaded software that
communicates with the database instance on the database server, and serves blocks to databases
based on the iDB protocol. It provides the advanced SQL offload capabilities, serves Oracle
blocks when SQL offload processing is not possible, and implements the DBRM I/O resource
management functionality to meter out I/O bandwidth to the various databases and consumer groups issuing I/O.
C: The MS is the primary interface to administer, manage and query the status of the Exadata cell. It works in cooperation with the Exadata cell command line interface (CLI) and EM Exadata plug-in, and provides standalone Exadata cell management and configuration. For example, from the cell, CLI commands are issued to configure storage, query I/O statistics and restart the cell. Also supplied is a distributed CLI so commands can be sent to multiple cells to ease management across cells.
F: Restart Server (RS) ensures the ongoing
functioning of the Exadata software and services. It is used to update the Exadata software. It also ensures storage services are started and running, and services are restarted when required.

None

To maximize storage savings with Hybrid Columnar Compression, data must be loaded using data warehouse bulk loading techniques. Examples of bulk load operations commonly used in data warehouse environments are:
* Insert statements with the APPEND hint
* Parallel DML
* Direct Path SQL*LDR
* Create Table as Select (CTAS)
Incorrect:
Not A, Not C: DML operations (INSERT/UPDATE) against a Hybrid Columnar Compressed table/partition can reduce the overall compression savings over time since data INSERTED/UPDATED via DML operations will not be compressed to the same ratio as data that is bulk loaded.

None

1: The Storage Server Patch is responsible for keeping our cell nodes always up-to-date, fixing possible problems, and this patch includes different component patches, like kernel patches, firmware, operation system, etc… for the Storage Server.
Incorrect:
3,4: security scan tools changes and Linux system performance optimization changes would be on the database server.

3. The database is started.
5. A query is issued against the MYOBJ_CTRL table that has a predicate OBJECT_ID=1500.
The Exadata cell services software conducts I/O requests on I MO storage regions.
7. MYOBJ_STATE’S region index is populated with high and low values for the OBJECT_ID column during the I/O request.
6. A subsequent query is Issued against the MYOBJ_CTRL table that has a predicate OBJECT_ID=2234.
2. cellsrv checks the high and low values, and determines the storage region does not contain any values meeting the predicate.
4. Physical I/O to the region is bypassed if the query selection falls outside the high/low storage index storage.
Note: Example:
Step 1 (step 5 in answer): The first time that each cell’s cell services software issued an I/O request to access extents
from the D14.MYOBJ_UNCOMP table, Exadata populated a region index for each storage index with the high and low values found for the OBJECT_ID column, based on the WHERE
OBJECT_ID BETWEEN 100 AND 200 query predicate.
Step 2 (step 6 in answer) : Subsequent queries against this table generated an iDB message instructing Exadata’s
cell services software to read the same sets of extents as the first query, but in this case the
region indexes would have been populated based on the I/Os read from the first query. Step 3: (step 2 in answer) Prior to issuing a physical disk read, cellsrv checks the high and low values stored in the
region index and if it determines that a storage region does not contain any values meeting the query predicate, bypasses the physical I/O to the region.